Opening
Regarding our stance, we are not only trying to disprove the Dracula and Renfield's argument that the doctors were negligent of their own work, but also to emphasize that it was the evil deed of the Dracula that resulted in Lucy's death. Despite the doctors' trying their best (we can see this from their willingness to donate their own blood to Lucy), she becomes frail after the night and the clear proof of the scar shows us blatantly that maybe Dracula is not that innocent. He had robbed a woman of her life, and robbed her lover of his soulmate, thus deserving a punishment that damns him to hell. As would be shown through the witnesses, there are striking proofs of the Dracula's evil works and the extent of damage it had on Lucy, thus solidifying our stance that Dracula is the root of this incident and that the doctor are innocent.

Quotations that can be used:
pg 117: "For two nights I had hardly had a wink of sleep, and my brain was beginning to feel the numbness which marks cerebral exhaustion."
pg 135: "I never saw in all my experience the Professor work in such deadly earnest."
Both doctors take their own blood to save Lucy every time she is bit by the Dracula.
pg 115: "A red mark on her throat... two punctures" -->clearly the work of Dracula.